[jhirasak]

You should not feel a bog or a change in the rate of acceleration if the correct spring is used. If you feel a bog, the spring is too soft and allows the secondaries to open too early. If you feel a change in acceleration when the secondaries open, the spring is too stiff and the secondaries need to open sooner. If there is no spring available between these two conditions, I would elect to use the stronger spring and avoid a bog during acceleration.